Oil engine



Aug. T1 1926.

c. L. cUMMlNs OIL ENGINE I Filed sept. s. 1925 Patented Ang. l'f, 1926.

UNITED STA-TES CLESSIE L. CUMMINS, 0F COLUMBUS, INDIANA..

oIL ENGINE.

-Application iled September 5, 1925. Serial No. 54,715.

This invention relates to oil burning engines of the type wherein the fuel is eX- ploded and burned by the heat of the air compressed by the piston withinthe combustion chamber of the cylinder. The principal object of my invention is to eect a more thorough atomization and vaporization of a charge of liquid fuel before the same is injected from a vaporizing chamber into the combustion chamber of the engine by a plunger or the like. To this end, I deposit a charge of liquid fuel into circuitous, tortuous or broken passages between the vaporizing chamber and the combustion chamber so th-at Vwhen compressed air is formed from the combustion chamber, through the tortuous passages into the vaporizing chamber, it picks up, atomizes and vaporizes the liquid fuel, after which a plunger in the vaporizing chamber is advanced to eject the dry gaseous mixture into the combustionV space through the passages,

the passages being tortuous or broken to' effect a more thorough break-up atomization and vaporization of the fuel.

With the above and incidentalobjects in view, the invention consists in certain novel features of construction and combination of parts, the essential elements whereof are described in detail hereinafter and illustrated in full in the accompanying drawings.

A Of 'said drawings, Fig. 1 is a. vertical fragmentary section taken through the upper end of a four cycle engine showing the preferred form of embodiment of my in- Y venticin applied thereto, and Fig. 42 is ar fragmentary section through an ejector embodying a modified form ofmy invention.

Fig. 1 shows, in section, the upper part of the cylinder 6 and reciprocating piston 7 of a four-cycle engine, to which, for the purpose of illustration, I have shown the preferred formof embodiment of my invention applied. An air intake valve 8 and an exhaust valve 9 may be of any approved construction.

The fuel injector, in general7 comprises a body member or plug 10, an ejecting plunger 11, operable in the central bore 11 of the plug, a cup-shaped member 12 fitting over and about the lower end of the plug,

' lower end of the central bore 11 a second cup-shaped member 13 of generally lsimilar shape, fitting over the inner cup" shaped member 12, and a fuel inlet valve 14 mounted in a bore 15 in the plug. The is closed by the cup 12 so that when the plun'ger 11 is elevated or retracted to the position shown 1n Flg. 1, an atomizing or vaporizing chamber C is formed under the plunger. The concave bottom of this chamber C, formed by the cup 12, is conical and of the same contour as the. lower convex conical end of the plunger l1, to form a seat therefor. The under side of the end of the cup 12 is cut away so that a cup-shaped space 16, having a fiat central portion and an annular conlcal portion, is formed between the cups 12 and 13. A plurality'of equally spaced ports or openings 17 are formed in the lower end of the cup 12 and communicate with the space 16 -near its upper rim. A plurality of equally spacedopenings or ports 18 are formed in the cup 13 and at their upper ends open into the conical portion of the space 16 but adjacent its fiat bottom. Opening upwardly into the flat portion of the space 16 is a conduit 19 which extendsv downwardly in the cup .13 and then upward-V ly through the cups12 and 13 and part of the plug 10, to the lower end of the bore 15, the upper end of this conduit 19 being closed by the needle valve 14.

The modification shown in Fig. 2 is very similar to the preferred form and I have -applied like reference numerals to the correused. The arms 21 and 22, shown diagrammatica-lly in dotted lines, may be considered as forming parts of'the'operating mechanisms for the plunger and valve respectively.

The operation s as follows: During the suction stroke of the piston 7, air is drawnv into the cylinder past the air valve 8. During this same stroke, the fuel valve 14 is elevated by its operating mechanism to unseat its lower end and a charge of liquid fuel, forced either by gravity or by a pump or other suitable means, flows through the vconduit 19 into the annular space 16 and the ports 17 and 18, this annular chamberand the ports being of just suiiicient volume to.

hold the entire charge of liquid fuel. This vbustion space.

charge of fuel, which is forced into the annular space 16 and the ports 17 and 18, has stood in the conduit 19 from the time it was deposited therein during the preceding suction stroke, so that each charge of fuel, w'hen it is deposited in the annular space and ports 17 and 18, is already heated which makes it more easily and thoroughly vaporized, while the passage of the fuel through the conduit 19 and into the annular space 16 and ports 17 and 18 serves to cool the projecting end of the injector and hence prevents t from getting so hot as to cause preignition or to cause a deposit of carbon thereon.

From the beginnin of the period when the liquid charge is eposited in the lower end of the vaporizing chamber until after the beginning or near the initial part of the compression stroke of the piston, I slowly elevate the plunger 11 from its lowermost position to the position shown in Fig. 1, so as to create a partial vacuum in the vaporizing chamber C for the purpose of preventing the partial vacuum in the combustion cham- Kber from causing any of the liquid fuel'to drip or be drawn into the combustion c'hamber. It will also be noted that the lower outer ends of the ports 18 are reduced insize so that these ends are very small in diameter, which also tends to hold the oil inthe ports and prevent it from dripping into the com- The plunger 11 is held in lretracted position during the remainder of the combustion stroke, and during such stroke part of the heated air, compressed in the combustion chamber and heated due to its compression, is forced through the ports 18, the annular chamber 16 and the ports 17 into the vaporizing chamber 16.' These streams of highly compressed heated air rushing through the openings and chamber 16 pick up the heated oil and thoroughly mix, atomize and vaporize it in the vaporizing chamber. Near the beginning of the power stroke of the piston, the plunger 11 is rapidly advanced or depressed until its lower end is seated and during this movement of the plunger the dry gaseous mixture of fuel and air is forced under high pressure out of the vaporizing chamber C through the restricted communicating openings 17, 16 and 18 into the combustion chamber of the cylinder, where it ignites or explodes, thereby greatly increasing the pressure in the combustion chamber and driving the piston downwardly.

The principal feature of my present -invention is depositing the liquid fuel in the broken or tortuous communicating pas-- sages between the vaporizing chamber C and the combustion space so that the fuel is more thoroughly and readily broken up and vaporized. The tortuous passages effect sudden or violent changes in the directions of movement of the fuel and air, when the liquid fuel is carried by the streams of air into the vaporizing chamber and when. the gaseous mixture is driven from the vaporizing chamber into the combustion space, and the globules or particles of oil are driven against different surfaces with the result that they are shattered or pulverized into smaller bits or atoms, thus making the vaporization of the fuel more rapid and thorough.

I do not intend to be confined to the precise structures shown and described as it is obvious that various modifications may be made without departing from the spirit of my invention.

I claimi l. In an oil engine, the combination of a cylinder and a -piston operable therein, a fuel vaporizing and injecting device comprising a vaporizing chamber having tortuous restricted passages communicating with the combustion space of said cylinder, a plunger reciprocable in said vaporizing chamber, means for discharging liquid fuel into said passages so that the fuel is heated, vaporized and mixed with the air forced from said combustion space through said passages onto said vaporizing chamber, and means for operating said plunger to eject the gasified mixture of air and fuel from said vaporizing chamber through said tortuous passages into said combustion space.

2. -In an oil engine, the combination of a cylinder and a piston operable therein, and a fuel vaporizing and injecting device comprising a vaporizing chamber having tortuous restricted passages communicating with the combustion space of said cylinder and of sufficient volume to hold the charge of liquid fuel, means for depositing the charge of liquid fuel, into said passages, so that the fuel is heated, vaporized and mixed with the air forced from said combustion space through said passages into said vaporizing chamber, a plunger operable in said vaporizing chamber, and means for operating said plunger to eject the gasiiied` mixture of air and fuel from said vvaporizing chamber through said tortuous passages into said combustion space.

3. In an oil engine, the combination of a cylinder and a pistonoperable therein, and a fuel vaporizing and injecting device comprising a chamber having tortuous restricted passages communicating with the combustion space of said cylinder, means for discharging liquid fuel into said passages during the suction stroke of the engine so that the fuel is heated, vaporized and mixed with the air forced from said combustion space through said'passages into said vaporizing chamber durin the compression stro e, and means or retracting said plunger while the fuel is being deposited in said tortuous passages and for advancing said plunger during the combustion stroke of the engine to ejectsaid gasified mixture of air and fuel from said chamber through said tortuous passages into said combustion space.

4l. ln an oil engine, the combination of a cylinder and a piston operable therein, and a fuel vaporizing and injecting device coinprising a body with its lower end projecting into the combustion chamber and having a vaporizing chamber, an annular space in its lower end, passages extending from the space to said chamber and passages out of registry with the first mentioned passages and extending from said s ace to the combustion chamber, means or depositing a charge of liquid fuel in said passages and space, a plunger reciprocable in said vaporizing chamber, and means or retracting and advancing said plunger so that when the plunger is retracted air is'forced from the combustion chamber through said passages and space into said vaporizing chamber and mixes with and vaporizes the liquid fuel and for advancing said plunger to eject the mixture and fuel from said vaporizing chamber through said passages and annular space into the combustion chamber.

5. ln an oil engine, the combination of a cylinder and a piston operable therein, and a fuel vaporizing and injecting device comprising a body with its lower end projecting into the combustion chamber of the cylinder and having a vaporizing chamber, an annular space in its lower end, ports extending from said space to said vaporizing chamber, ports out of registry with the first mentioned ports and extending from said annular space to the combustion cham- 40 ber yand a conduit opening upwardly into the center of said oil space to deposit a charge of oil therein and in said ports, a plunger operable in said vaporizing chamber, and means for retracting and advancing said plunger so that when the plun er is retracted heated compressed air is orced from the combustion chamber through' said ports and space into said vaporizing chamber to vaporize the fuel and when the plunger is advanced the vaporized mixture v of air and fuel is forced from said vaporizing chamber through said ports and space into the combustion chamber. 6. In an oil engine, the combination of a cylinder, having a combustion chamber, and a piston operable therein, and a fuel vaporizing and injecting device comprising a plug having a vaporizing chamberthe'rein, a cup on the end of the plug and having ports, a second cup fitting over the first cup and having ports out of registr with the first mentioned ports, the cups orming a space between them with which the ports of both cups communicate, a plunger in said vaporizing chamber, means or depositing fa l. charge of liquid fuel into said space and' ports so that compressed air forced from the combustion chamber carries the liquid fuel into the vaporizing chamber and vaporizes the same, and means for retraeting said` plunger to permit the heated air to enter the vaporizing chamber and for advancing.;` the plunvfer to eject all of the vaporize mixture the combustion chamber.

CLESSIE L. CUMMINS.

rom said vaporizing chamber into 

